In Australian patent specification No. AU-48947/93 (Patent Serial No. 651285) there is described a process for manufacturing bodies composed of a binder mixed with a feed material including rice hulls and/or particles obtained by comminuting rice hulls. The binder comprises a beat curable composition. The mixture of the feed material and binder is formed into the generally desired shape of the body e.g. in a mould or in a press, and the binder is cured to form an adherent body having substantially the required shape, e.g. by applying to the formed shape an RF field of a suitable frequency and intensity and for a suitable period of time to cause dielectric heating within the mixture so as to cure the binder to form the final adherent body. The body is then removed from the mould or press. Reference may be made to this patent specification for further background information particularly in relation to rice hulls and their properties and preparation.
A further patent specification AU-2001100327 by the present applicant further describes processes for forming bodies by extrusion using rice hulls. This patent specification is also incorporated herein in full by cross-reference for the purpose of providing further background information about particulates, fillers, binders, additives, reinforcing, etc that can be used in such bound bodies.
The above references to and descriptions of prior proposals or products and processes are not intended to be, and are not to be construed as, statements or admissions of common general knowledge in the art.
Problems with RF heating and curing, particularly if continuous production of bound bodies is attempted, are outlined later in relation to FIGS. 1 and 2 of the drawings. These figures however do not depict known or published apparatus to the applicant's knowledge, but rather they are used to illustrate difficulties the inventor faced and overcame with the present invention.